Rheumatoid arthritis (RA) is a chronic inflammatory disease of the joint, for which treatment strategies have remained suboptimal for a long time. The treatment of RA has changed dramatically during the past decade due to the better understanding of its pathogenesis. Especially in early RA, early diagnosis and appropriate treatment is highlighted, with the treatment goal being clinical remission. In order to prevent joint damage and long-term disability, early use of disease-modifying anti-rheumatic drugs (DMARDs) is a key. Aggressive treatment such as combination of DMARDs and glucocorticoids or biological agents can induce a high rate of remission, suppression of joint damage and provide better outcome than DMARD monotherapy in early RA and should be considered in high-risk patients. Timely adjustment of therapy until patients have achieved low levels of disease activity is also crucial. On the other hand, treatment for osteoarthritis has mainly been focused on the alleviation of pain, while the goal of disease modification still remains elusive. Because the long-term use of non-steroidal anti-inflammatory agents poses significant risk of adverse events on the elderly, nonpharmacologic therapy including weight reduction, muscle strengthening, and exercise is recommended first. Recent advances in the understanding of the pathogenesis of osteoarthritis may provide a clue that will ultimately lead to disease modification.